PSC_IMR
WR2(sc, PSC_IMR, 0); /* no PSC interrupts; BestComm drives playback */
PSC_WRITE_2(sc, PSC_IMR, sc->sc_imr);
PSC_WRITE_2(sc, PSC_IMR, sc->sc_imr);
PSC_WRITE_2(sc, PSC_IMR, sc->sc_imr);
PSC_WRITE_2(sc, PSC_IMR, sc->sc_imr);
PSC_WRITE_2(sc, PSC_IMR, sc->sc_imr);